Google Analytics can help you learn more about the behavior of your client’s customer’s, because it shows you how:
Likely they are to become a regular customer
Likely they are to click her ads
They interact with her website
They perceive her products
Explanation: Google Analytics has a powerful segmentation engine. Instead of looking at your audience in large bunches, you can break it down into its component parts and understand how each part interacts with your site—then bid, message and direct traffic accordingly. Read more here
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